Despite the best efforts of some very good teachers, many things in American history remain murky to me. For instance: Who bribed whom to cause the Teapot Dome scandal? What did the Smoot-Hawley Tariff tax? And why did we fight the War of 1812?

Add to this list the story of John Brown’s 1859 raid on Harpers Ferry. My favorite elementary school teacher called John Brown a hero, while my crisply edited high school textbook branded him a crazed vigilante. But exactly what he did and why I have never fully grasped.

That is, not until I picked up Tony Horwitz’s absorbing new book Midnight Rising: John Brown and the Raid that Sparked the Civil War. Horwitz, a Pulitzer Prize-winning journalist and author with a gift for writing engagingly about many things, is perhaps best known for “Confederates in the Attic,” his 1998 book about America’s ongoing obsession with the Civil War.

This time, Horwitz – dismayed that history sometimes treats Brown and his dramatic raid on Harpers Ferry as a mere “speed bump” in the race toward the Civil War – turns the clock back to 1800, the year that Brown was born into an infant United States, a country that was still a “preindustrial society of five million people,” of whom “almost 900,000 were enslaved.”

Even as a small boy, Horwitz notes, Brown showed signs of “a truculent and nonconformist spirit.” That spirit, apparently, was roused to deep agitation when Brown, at the age of 12, saw a slave boy beaten with iron shovels. He would later write that this event jolted him into awareness of “the wretched, hopeless condition, of Fatherless & Motherless slave children” and marked the beginning of his “Eternal war with slavery.”

Horwitz does a good job of marching quickly but clearly through the escalating tensions over slavery in the United States of Brown’s adult years. Brown was hardly the only anti-slavery activist horrified by events like the passage of the Fugitive Slave Act in 1850. And he was only one of thousands of Americans who moved to Kansas in the 1850s with the express purpose of influencing that state’s vote to become either “free” or “slave.”

But Brown was one of only a tiny minority of Kansans ready to back his beliefs with violence. He launched several violent raids either to free slaves or simply to frighten (or kill) those who expressed pro-slavery attitudes. He grew his beard long and at least one observer remarked on his “glittering gray-blue eyes” with “a little touch of insanity.”

But Horwitz does a good job of painting a more three-dimensional portrait of his subject. Brown was also a loving husband and father who, in many ways, genuinely lived his Christian principles. One black activist of the era wrote that Brown – different from some other white crusaders – showed “no offensive contempt for the Negro while working in his cause.” He noted that Brown treated people of all kinds and classes, black and white, as equals and maintained a home “wherein no hateful prejudice dared intrude its ugly self.”

Brown’s eventual plan to march into Virginia with fewer than 20 men, raid a federal armory, and liberate all the state’s slaves horrified even most of his closest allies. But to Brown’s way of thinking, true patriotism required nothing less. Slavery was a violation of the principles of both Brown's God and his country – and only a second revolution could reinstate justice.

Horwitz’s description of the little band of idealists and adventurers who signed on for Brown’s offensive – including five black men and two of Brown’s own sons – is both fascinating and touching. His careful recreation of the bloody events of October 16, 1859, the day of Brown’s disastrous raid on Harpers Ferry, is both suspenseful and heartwrenching. (Within a mere 36 hours, Brown’s second American Revolution was all over, with most of Brown's tiny posse either captured or dead.)

But perhaps most remarkable in “Midnight Rising” is the story of the months after the raid during which Brown was imprisoned and sentenced to death. His courage and comportment as a prisoner were so impressive that he ended up scoring a propaganda victory perhaps greater than the military victory he had dreamed of. With impeccable manners and calm, persuasive speech, Brown told his captors exactly why he behaved as he did, invoking the Bible and the principles upon which the United States was built. Brown was “fanatic, vain and garrulous, but firm, and truthful, and intelligent,” admitted no less an enemy than slave-holding Virginia governor Henry Wise.

Brown was eventually hanged – along with his surviving confederates – but not before making himself a hero and martyr. When Lincoln finally declared war in 1861, it seemed to some that the country was finally just catching up to John Brown.